Elderly-onset rheumatoid arthritis receives less aggressive therapies than young-onset rheumatoid arthritis in an Argentinian cohort.

Objectives: When rheumatoid arthritis (RA) starts after the age of 60 it is called elderly-onset rheumatoid arthritis (EORA) and when it starts earlier, young-onset rheumatoid arthritis. (YORA). There are few Latin American studies that compared both groups.

Toll-like receptor expression and functional behavior in platelets from patients with systemic lupus erythematosus.

Background: Multiple blood cell abnormalities participate in the development of inflammation in systemic lupus erythematosus (SLE). Although platelets have been suggested as one of these contributors through the release of their content during activation, there are limited specific data about their role as immune players in SLE.

Materials And Methods: Thirteen SLE patients were included.

Social networks as education strategies for indigenous patients with rheumatoid arthritis during COVID-19 pandemic. Are they useful?

Introduction: The use of online education strategies has been introduced as a tool to support health care in patients with rheumatic disease. However, it is important to consider the patient's sociocultural environment.

Objective: To design and assessment of bilingual audiovisual material acceptability, by means of two social networks, for patients with rheumatoid arthritis (RA) in the qom community in Argentina.

Multicenter lupus register from Argentina, the RELESSAR database: Influence of ethnicity on disease phenotype.

Objective: The objective is to describe the main characteristics of patients with systemic lupus erythematosus (SLE) in Argentina and to examine the influence of ethnicity on the expression of the disease.

Patients And Methods: RELESSAR is a multicentre register carried out by 106 researchers from 67 rheumatologic Argentine centres. It is a cross-sectional study of SLE (1982/1997 ACR) patients.

Validation and adaptation of the Spanish version of the systemic lupus activity questionnaire (S-SLAQ) in an Argentinean population.

Objectives: To validate the systemic lupus activity questionnaire (SLAQ) in Spanish language.

Methods: The SLAQ questionnaire was translated and adapted in Spanish. Consecutive SLE patients from 8 centers in Argentina were included.

Pathogenic mechanisms contributing to thrombocytopenia in patients with systemic lupus erythematosus.

SummarySystemic lupus erythematosus (SLE) is an autoimmune condition developing thrombocytopenia in about 10-15% of cases, however, mechanisms leading to low platelet count were not deeply investigated in this illness. Here we studied possible causes of thrombocytopenia, including different mechanisms of platelet clearance and impairment in platelet production. Twenty-five SLE patients with and without thrombocytopenia were included.

Anti-RNA polymerase III antibodies in systemic sclerosis: Multicentric study from Argentina.

Objective: To describe the frequency of anti-RNA polymerase III antibody in patients with Systemic Sclerosis (SSc) of a group of healthcare centres from Argentina and to explore differences among patients with positive and negative anti-RNA polymerase III antibody.

Patients And Methods: Data from clinical records, anamnesis and physical examination were collected from 135 patients with SSc (ACR/EULAR 2013). A serum sample from each patient was obtained for the detection of anti-RNA polymerase III IgG antibodies by ELISA.

Characterization of Patients With Dermatomyositis According to Anti-Melanoma Differentiation-Associated Gene-5 Autoantibodies in Centers from 3 Latin American Countries: A Cohort Study.

Background/objective: The anti-melanoma differentiation-associated protein 5 (MDA5) autoantibodies have been associated with a high frequency of interstitial lung disease (ILD) and rapidly progressive ILD (RP-ILD) in dermatomyositis (DM) patients, mainly in Asian subjects. However, there is scarce information about these parameters in Latin American patients.

Method: This was a medical records review cohort study that included classic DM (CDM) and clinically amyopathic DM (CADM) patients from 3 Latin American countries (Argentina, Brazil, and Mexico).

Myositis-specific antibodies and clinical characteristics in patients with autoimmune inflammatory myopathies: reported by the Argentine Registry of Inflammatory Myopathies of the Argentine Society of Rheumatology.

Introduction/objectives: To describe clinical features in patients with inflammatory myopathies (IMs) from the Argentine Registry of Inflammatory Myopathies, and their relationship with myositis-specific antibodies (MSAs).

Methods: This cross-sectional study included 360 adult patients with dermatomyositis (DM), polymyositis (PM), and inclusion body myositis. Demographics, clinical, and serological characteristics were retrospectively recorded (2016-2019).

Anti-RNA Polymerase III Antibodies in Systemic Sclerosis: Multicentric Study from Argentina.

Objective: To describe the frequency of anti-RNA polymerase III antibody in patients with Systemic Sclerosis (SSc) of a group of healthcare centres from Argentina and to explore differences among patients with positive and negative anti-RNA polymerase III antibody.

Patients And Methods: Data from clinical records, anamnesis and physical examination were collected from 135 patients with SSc (ACR/EULAR 2013). A serum sample from each patient was obtained for the detection of anti-RNA polymerase III IgG antibodies by ELISA.

Clinical characteristics and prognostic factors in an Argentinian cohort with ANCA-associated vasculitis.

ANCA-associated vasculitis is a heterogeneous group of rare autoimmune conditions of unknown cause. Clinical characteristics and prognostic factors were analyzed in 47 patients: 20 (42.5%) with granulomatosis with polyangiitis, 17 (36.

Access to healthcare system of indigenous communities with musculoskeletal disorders and rheumatic disease in Chaco, Argentina: a qualitative study.

Introduction/objectives: The objective of this study is to describe the local healthcare system from the perspective of the health professionals, community health workers, and local representatives of the qom community living in the province of Chaco, Argentina.

Methods: A qualitative study, with an ethnographic approach, was carried out using two techniques: non-participant observations and semi-structured interviews. A guide for the interviews was designed and developed by a multidisciplinary group of GLADERPO researchers.

Myositis-Specific Antibodies and Myositis-Associated Antibodies in Patients With Idiopathic Inflammatory Myopathies From the PANLAR Myositis Study Group.

Background: Dermatomyositis (DM) and polymyositis (PM) are forms of idiopathic inflammatory myopathies (IIMs), which are associated with the production of autoantibodies that are useful in the diagnosis and prognosis of the disease.

Objective: The aim of this study was to determine the frequency of antinuclear autoantibodies (ANAs), myositis-specific autoantibodies (MSAs), and myositis-associated autoantibodies (MAAs) in 6 Latin American countries.

Methods: Two hundred ten patients with IIM were included in this cross-sectional study from 2014 to 2017: 112 from Mexico, 46 from Colombia, 20 from Peru, 16 from the Dominican Republic, 10 from Argentina, and 6 from Guatemala.

Autoantibodies to Mi-2 alpha and Mi-2 beta in patients with idiopathic inflammatory myopathy.

Objectives: The objective of this study was to compare the results obtained from different assays for the detection of anti-Mi-2 antibodies, which are important markers in the diagnosis of DM.

Methods: The study included 82 patients (68 females/14 males), most of whom had DM (n = 57), followed by PM (n = 16) and juvenile DM (n = 9). All samples were tested using a novel particle-based multi-analyte technology (PMAT) (Inova Diagnostics, research use only) in parallel with a line immunoassay (LIA: Euroimmun).

Evaluation of the Educational Needs in Argentine Patients with Rheumatoid Arthritis Using the SpENAT Questionnaire.

Background: The SpENAT, a Spanish version of the Educational Needs Assessment Tool, is a self-completed questionnaire that assesses educational needs (ENs) with the purpose of providing tailored and patient-centered information. It consists of 39 questions grouped into the 7 following domains: Pain management, Movement, Feelings, Arthritic process, Treatments, Self-help measures and Support system.

Objectives: The objective of the study was to describe the ENs of rheumatoid arthritis (RA) patients using the SpENAT and to determine the main sources of information consulted by these patients.

[Dermatomyositis associated with anti-MDA5 autoantibody].

Dematomyositis is an idiopathic inflammatory myopathy with a variable clinical spectrum. In recent years, a number of myositis-specific antibodies have been identified including anti-MDA5, which is us eful for diagnosis, prognosis and classification of the diverse clinical forms of the disease. This antibody is associated with cutaneous ulcers, rapidly progressive interstitial lung disease, early mortality and poor prognosis, so the detection of this antibody in a suitable clinical context, raises the need for an aggressive immunosuppressive treatment.

Cut-off values of immunological tests to identify patients at high risk of severe lupus nephritis.

Cut-off values for anti-dsDNA, anti-nucleosome and anti-C1q antibodies tests and for complementmediated hemolytic activity (CH50) were explored to identify patients with high risk of developing severe lupus nephritis (LN). Forty-one patients with confirmed systemic lupus erythematosus (SLE) were identified; their levels for the three antibodies and complement had been measured on a same serum sample. These patients were classified based on the presence of renal involvem ent; sixteen had active proliferative LN.

[Genetic polymorphisms of thiopurine methyltransferase and incidence of adverse events in patients with medical indication of azathioprine].

Azathioprine is a thiopurine which has a narrow therapeutic index and marked hematological and hepatic toxicity. Thiopurine s-methyltransferase is an enzyme involved in the metabolism of thiopurines. Mutations in the gene that encodes the enzyme may augment the risk of adverse events.

Autoantibodies in adult patients with idiopathic inflammatory myopathies in Buenos Aires.

The idiopathic inflammatory myopathies(IIM) are a heterogeneous group of diseases of the skeletal muscle. On the basis of clinical, serologic and histological differences, they are classified in dermatomyositis (DM), polymyositis (PM), inclusion body myositis and immunomediated necrotizing myopathy. Autoantibodies directed against nuclear and cytoplasmic antigens are present with variable frequencies among studies.

Long-term Outcome of Lupus Nephritis Class II in Argentine Patients: An Open Retrospective Analysis.

Background: There is controversy in medical literature over the outcome of patients with lupus nephritis (LN) class II. The aim of this study was to explore the risk of histological transformation (HT) and possible factors related to negative response to treatment in patients with mesangial LN class II.

Methods: A retrospective and multicenter study was carried out that includes patients who had received a diagnosis of LN class II on their first renal biopsy.

Association between the presence of anti-C1q antibodies and active nephritis in patients with systemic lupus erythematosus.

Lupus nephritis (LN) is a severe complication of systemic lupus erythematosus (SLE). A retrospective analysis was carried out on a group of 24 patients with SLE to evaluate whether the presence of anti-C1q antibodies (anti-C1q) is related to renal involvement and to explore the behaviour of anti-C1q with respect to LN during a four-year follow-up period. A first serum sample stored at the serum bank, taken not more than three years after SLE diagnosis and one serum sample per year for the subsequent four years were used to detect anti-C1q.

Childhood systemic lupus erythematosus in Latin America. The GLADEL experience in 230 children.

To evaluate disease characteristics of childhood onset SLE in Latin America and to compare this information with an adult population in the same cohort of GLADEL. A protocol was designed as a multicenter, multinational, inception cohort of lupus patients to evaluate demographic, clinical, laboratory and serological variables, as well as classification criteria, disease activity, organ damage and mortality. Descriptive statistics, chi square, Fisher's exact test, Student's t test and multiple logistic regression were used to compare childhood and adult onset SLE.